Field of the Invention
The present invention relates to a pharmaceutical vaccine composition for a human cervical cancer, a method for preventing a human cervical cancer, and a method for preparing a human papillomavirus (HPV) L1 virus-like particle (VLP).
Description of the Related Art
More than 80 types of Human Papillomavirus (HPV) have been known and about 30 types causes cervical infection through sexual contact, of which half types have been known to be related with cervical cancer (Zur Hausen H, Mol. Carcinogenesis 8: 147-150 (1988)). Of them, it has been known that a cancer rate of women infected with HPV type 16 and 18 is about 50-fold higher than that of normal women, and HPV type 16 and 18 are infected into epithelial cells of genital organ, resulting in cervical cancer via malignant transformation (Zur Hausen H, Mol. Carcinogenesis 8: 147-150 (1988); Hausen, Biochemica. Biophysica. Acta. 1288: 55-78 (1996)).
Current vaccines for preventing a cervical cancer have been developed using high risk type HPV virus-like particles (VLPs). VLP is a major capsid protein (L1 protein, about 55 kDa) of HPV, and has various advantages as a vaccine candidate, including: (a) an ability self-assembled to VLP without gene product of other virus like that as observed in natural HPV virion; (b) maintenance of long-term immunity; and (c) a highly efficiency due to a type specificity against a gene type.
‘Gardasil’ (Merck & Co., Inc.) using VLPs is a vaccine developed using each antigen against HPV type 6, 11, 16 and 18, and ‘Alum’ as the most common immunoadjuvant. ‘Cervarix’ (GlaxoSmithKline Plc.) is a vaccine developed using HPV type 16 and 18 as a representative factor triggering a cervical cancer and ‘AS04’ as an immunoadjuvant developed independently.
Alum used as an immunoadjuvant in the ‘gardasil’ has been utilized as a vaccine for diphtheria, tetanus and hepatitis type B, and it was reported that Alum enhances antigen stability and induces release of cytokines. However, the use of gardasil is limited because: (a) it is impossible to lyophilize or freeze vaccine; (b) it is not effective in all antigens; and (c) it promotes only humoral immune response.
AS04 contained in the Cervarix of GSK has been developed for the purpose of inducing potent and persistent immune responses, and is composed of aluminum hydroxide and monophosphoryl lipid A (MPL). The term “MPL” used herein refers to an immunostimulatory substance capable of directly activating a critical immune response, playing a role in enhancement of immune response against an antigen involved in the vaccine.
Recently, immunoadjuvants have been newly focused and utilized in various vaccines such as cervical cancer vaccines and influenza vaccines. Of them, bacterial DNA received attention as an anti-cancer agent since 1960's, and is successively researched up to now. However, bacterial DNA has not been used as an anti-cancer agent due to its low efficacy (Glick, J. L. The specificity of inhibition of tumor cell viability by DNA. Cancer Res. 27: 2338 (1967)). In spite of this defect, it was demonstrated that bacterial DNA is known to activate various immune cells without serious side effects, and has many advantages as an adjuvant (McCluskie M J, et al., CpG DNA is a potent enhancer of systemic and mucosal immune responses against hepatitis B surface antigen with intranasal administration to mice. J Immunol. November 1; 161 (9): 4463-6 (1998)).
For these effects of bacterial DNA, Yamamoto et al. in Japan argument that palindromic sequences containing CG play a crucial role in effects of bacterial DNA which are demonstrated by Krieg et al. (Yamamoto S. et al. Unique palindromic sequences in synthetic oligonucleotides are required to induce IFN and augment IFN-mediated natural killer activity. 3. Immunol. 148: 4072 (1992); Krieg A M, Antitumor applications of stimulating toll-like receptor 9 with CpG oligodeoxynucleotides. Curr. Oncol. Rep. March; 6 (2): 88-95 (2004)). Based on CpG-related studies from the middle of 1990's, the concern for DNA anti-cancer agent leaded to deduce a probability of synthetic DNA (CpG-ODN) containing unmethylated CG as an anti-cancer agent, for example a study for S substitution in diester bonds to inhibit short synthetic DNA degradation. In this connection, CpG-ODN-related products were utilized in a clinical trial as an anti-cancer agent as well as an adjuvant (colevpharma).
However, there remains to be solved some problems including immunogenicity and still low anti-cancer activity of S substitution in diester bonds of CpG-ODN. On current clinic, CpG 7909 is a phosphothioate oligonucleotide which induces anti-DNA Ab (Clin Immunol. August; 100 (2): 157-63 (2001)), and is closely associated with autoimmune disorders such as SLE (systemic lupus erythematosus) (J Clin Immunol. July; 6 (4): 292-8 (1986)). In addition, it has been known that phosphothioate structure functions as TI Ag, contributing to disturbance of immune protection against infections (Mol Immunol. December; 35 (18): 1161-70 (1998)).
In LPS known to have anti-cancer effect since 1950's, utilization of LPS was difficult because LPS in a range of ng results in death by sepsis. It is general opinion that the link between LPS and DNA causes serious cytotoxicity, and thus the elimination of LPS is understood as very important process in DNA-related medicaments (Gao J J. et. al, Bacterial DNA and lipopolysaccharide induce synergistic production of TNF-alpha through a post-transcriptional mechanism. J Immunol 166 (11): 6855-60 (2001)). In respect with efficacies, it should be considered that immune responses stimulated by LPS are much stronger than those by DNA whereas are Th2-type responses, not Th1-type which is important to anti-cancer, supposing LPS is not suitable as an anti-cancer agent (Lebman DA et at Interleukin 4 causes isotype switching to IgE in T cell-stimulated clonal B cell cultures. 3 Exp Med. September 1; 168 (3): 853-62 (1988)). Given that Th2-type immune activity inhibits Th1-type immune activity, it was very difficult to utilize LPS as an anti-cancer agent due to Th2-type immune activity stimulated by LPS (Rengarajan J et al. Transcriptional regulation of Th1/Th2 polarization. Immunol Today. October; 21 (10): 479-83 (2000)).
A variety of attempts to LPS detoxification have been studied, leading to successfully reduce its cytotoxicity through removal of polysaccharide chain or deacylation of lipid A (Katz S S et al Deacylation of lipopolysaccharide in whole Escherichia coli during destruction by cellular and extracellular components of a rabbit peritoneal inflammatory exudate. J Biol Chem. December 17; 274 (51): 36579-84 (1999)). For example, monophosphoryl lipid A (MPL) is obtained by phosphorylation of lipid A in which polysaccharide chain of LPS is eliminated to develop an immunotherapeutic anti-cancer agent. However, its efficacy is known to be quite low (corixa).
On the other hand, the present applicants have already developed a novel immunoadjuvant to complement drawbacks of the above-mentioned immunoadjuvants (Korean Patent No. 0740237 (2007.07.10)).
Throughout this application, various patents and publications are referenced and citations are provided in parentheses. The disclosure of these patents and publications in their entities are hereby incorporated by references into this application in order to more fully describe this invention and the state of the art to which this invention pertains.